I used fossil oil at 20:1 for the first 2 gallons, then fossil oil at 25:1 for the second 2. Then I went to synthetic oil at 30:1 although that may be a little too thick. The reasoning is that the fossil oil will allow the engine to wear in properly. Then you switch to synthetic to keep it from wearing out.
As far as use I would say to take it easy for the fist half hour or so. If there are any major problems with the build they should show by then. From there ride it like you are going to normally.
If it can't be broken I'll find a way!
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